1. Field of the Invention
The present invention relates to anode active materials, methods of preparing the same, and anodes and lithium batteries containing the anode active materials. More particularly, the invention is directed to an anode active material including crystalline silicon which undergoes insignificant volume changes.
2. Description of the Related Art
Non-aqueous electrolyte secondary batteries, which include anodes comprising lithium compounds, exhibit high voltages and high energy densities, and have therefore been widely researched. Lithium metal has been studied as an anode material because of its high capacity. However, when metallic lithium is used as the anode material, lithium dendrites are deposited on the surface of the metallic lithium during charging. The lithium dendrites reduce the charge/discharge efficiency of the battery, and can cause short-circuits. Furthermore, lithium metal anodes can be unstable due to the high reactivity of lithium.
On the other hand, carbon-based anodes have decreased expansion and contraction volumes during charge/discharge cycles relative to anodes made of lithium or lithium alloys. However, carbon-based anodes have reduced capacity (about 350 mAh/g) and initial charge and discharge efficiency relative to lithium.